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以降低合成橡胶生产厂后处理装置各种振动机造成的地基振动为目的,对双质体振动机的隔振效能进行了定量分析。通过生产实践,总结了单质体振动机、非平衡型双质体振动机和对称平衡型双质体振动机的优缺点,给出了后者的设计计算数据。经综合分析和生产考核,认为采用对称平衡型双质体振动机是降低地基振、降低噪音、延长振动机的运转周期和使用寿命的最佳方法。 相似文献
14.
通过对自主研发的Sampave等3种改性沥青结合料和不同级配的应力吸收层沥青混合料进行低温弯曲和低温蠕变试验,分析沥青结合料和矿料级配对应力吸收层沥青混合料低温抗裂性能的影响.结果表明:自主研发的Sampave特种改性沥青混合料具有优良的低温抗裂性能,但单一改性剂SBR改性沥青并不能达到应力吸收层沥青结合料的性能要求;矿料4.75 mm、0.075 mm筛孔通过率对其低温抗裂性能影响较敏感. 相似文献
15.
研究了H2S吸收液中酸性杂质对吸收平衡的影响,研究表明,H2S在脱硫液中的溶解量随着活性氨的增加而提高,随杂质含量的增加而减少,对于酸性物较多的吸收液,应相应提高总氨量,以提高脱硫液中的活性氨含量。 相似文献
16.
Haiming Zhang Biao Zhao Huimin Xiang Fu-Zhi Dai Zhili Zhang Yanchun Zhou 《Journal of the American Ceramic Society》2021,104(5):2213-2224
The electromagnetic (EM) wave absorbing properties of Cr2AlB2 powders and those after high-temperature oxidation were investigated. Coupling of magnetic and dielectric loss enables Cr2AlB2 with good absorption properties. The minimum reflection loss (RL) value is −44.9 dB at 8.5 GHz with a thickness of 2.7 mm, and the optimized effective absorption bandwidth (EAB) is 4.4 GHz (13.0-17.4 GHz) with a thickness of 1.6 mm. After oxidation at 750, 900, and 1000°C for 2 h, the minimum RL values, respectively, are −23.9 dB (17.5 GHz, 1.5 mm), −41.4 dB (16.5 GHz, 1.5 mm), and −39.5 dB (8.0 GHz, 3.0 mm); and the corresponding EAB values, respectively, are 3.8 GHz (13.6-17.4 GHz, 1.7 mm), 4.1 GHz (13.5-17.6 GHz, 1.6 mm), and 4.4 GHz (13.0-17.4 GHz, 1.7 mm). With an absorber thickness of 1.5-4.0 mm, the EAB with a RL value of less than −10 dB can be tuned in a broad-frequency range 5.0-18.0 GHz, which basically covers C (4-8 GHz), X (8-12 GHz), and Ku (12-18 GHz) bands. These results demonstrate that Cr2AlB2, as a high-efficient and oxidation-resistant absorber, is a promising candidate for microwave absorption applications and can retain good EM wave absorbing properties after high-temperature oxidation. 相似文献
17.
F.X. Wang X.P. Gao Z.W. Lu S.H. Ye J.Q. Qu F. Wu H.T. Yuan D.Y. Song 《Journal of Alloys and Compounds》2004,370(1-2):326-330
In this work, effects of partial substitution of Mg, Ni with AB2 in Mg-based alloy and subsequent surface modification by further ball-milling with carbon nanotubes (CNTs) on electrochemical properties were investigated. Mg1.9(AB2)0.1Ni0.8 (AB2=LaNi2, LaNiCo and LaNiMn) alloys were prepared by solid-state diffusion method, the nanocrystalline Mg-based alloys were prepared by ball-milling the mixture of obtained Mg1.9(AB2)0.1Ni0.8 alloys and nickel powder. It was found that the electrochemical capacities of nanocrystalline Mg1.9(AB2)0.1Ni1.8 alloys were measured to be 460–490 mAh/g. The nanocrystalline Mg-based alloys containing carbon nanotubes (10 wt.%) obtained by ball-milling after 60 min were demonstrated to show improved electrochemical properties with respect to the original nanocrystalline Mg-based alloys. The electrochemical reaction activity was detected by electrochemical impedance spectra (EIS). Raman and X-ray photoelectron spectroscopy (XPS) proved the interaction between Mg1.9(AB2)0.1Ni1.8 alloys and carbon nanotubes after ball-milling, which resulted in an increase in the surface Ni/Mg ratio. 相似文献
18.
Michael P. Balogh Camille Y. Jones J.F. Herbst Louis G. Hector Jr. Matthew Kundrat 《Journal of Alloys and Compounds》2006,420(1-2):326-336
Half-Heusler compounds of Sn-doped TiCoSb “TiCoSnxSb1−x (x = 0.0, 0.01, and 0.05)” were prepared and their thermoelectric properties were measured above room temperature. From the EDX analysis, all the samples have three phases: the TiCoSnxSb1−x, Co-rich, and Ti-rich phases. The values of the thermoelectric power increase with Sn doping, and a positive thermoelectric power is obtained in the sample of TiCoSn0.05Sb0.95. The thermal conductivity decreases both with increasing temperature and with Sn content. The maximum value of ZT for p-type material is 0.030 at 988 K in the sample of TiCoSn0.05Sb0.95. 相似文献
19.
M. Yoshida H. Ishibashi K. Susa T. Ogura E. Akiba 《Journal of Alloys and Compounds》1995,230(2):100-108
The crystal structure, hydrogen absorbing properties and electrode performance of Laves phase alloy systems, Sc---Zr---Ni---Mn and Sc---Ni---V systems, were studied by optical and scanning electron microscopy, X-ray powder diffraction, pressure-composition isotherm and electrochemical measurements. C14 and C15 Laves phases and minor ScNi-related phase were found in the Sc---Zr---Ni---Mn alloy system. The ScNi-related phase was composed of Sc, Zr and Ni elements. Two kinds of minor phase, BCC and ScNi-related phases, were identified in addition to the C15 phase in the Sc---Zr---Ni---V alloy system. The BCC contained mainly the element V. The ScNi-related phase contributed to an increase in the hydrogen capacity, but those in the V alloy system did not. The multiphase anode with a large amount of the ScNi-related phase showed a low durability against the KOH electrolyte. The substitution of Zr by Sc led to an improvement in the initial activation of the anode, but there was not a clear correlation between the presence of the multiphase in the anode and the rate capability. 相似文献
20.
分析了低温预氧化过程对聚碳硅烷(PCS)先驱体结构的影响,研究了不同预氧化温度和时间下SiCf/SiC复合材料室温和高温介电性能的演变规律。结果表明:经预氧化处理后基体中的氧含量增加,生成具有低介电常数的Si CxOy相,且其含量随着预氧化温度的升高或时间的延长逐渐增加,SiC微晶和自由碳的含量均减少,因此SiCf/SiC复合材料的复介电常数明显降低,同时高温复介电常数的升高幅度显著减小。经260℃-6 h预氧化处理后,700℃时复合材料在整个X波段的反射率均达到-8 d B以下,高温吸波性能得到有效改善。 相似文献